Oklahoma licensure for plumbing contractors is administered by the Construction Industries Board under the Plumbing License Law of 1955. The unlimited Plumbing Contractor sits two open-book portions through PSI — a trade portion of 85 questions in 180 minutes and a Plumbing Business and Law portion of 50 questions in 120 minutes — with the trade standard at 70% (60 of 85) effective November 1, 2026 and the Business and Law standard at 75% (37 of 50). The PassProfessor Oklahoma Plumbing Contractor program prepares candidates for both portions and for the Oklahoma licensing structure around them.
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The name matters: there is no Oklahoma master plumber licence
Oklahoma’s top plumbing tier is the Plumbing Contractor, and this page uses that name throughout because Oklahoma law retired the older one. Title 59, section 1003(7) defines the older term only to retire it: a person formerly known by that term is henceforth to be known as a plumbing contractor. The rule class list contains no class under the retired name. Preparation material that offers an Oklahoma licence under the retired name is offering a credential that does not exist.
Two contractor licences stand at the top of the system, and this program keeps them distinct. The Plumbing Contractor licence covered by this page is the unlimited contractor licence. The Residential Plumbing Contractor licence is a separate licence, examined on a separate residential trade examination — stated separately wherever this page’s facts distinguish it, beginning with the examination references below, where the residential trade examination is built on the International Residential Code rather than on the plumbing and fuel gas codes that govern the unlimited examination.
What the unlimited licence authorises is stated in the statute’s own terms: a plumbing contractor is a person skilled in the planning, superintending, and practical installation of plumbing, licensed as a plumbing contractor, who may operate as an individual, firm, partnership, limited liability company, corporation, or other legal entity to engage in the business of plumbing — contracting to do plumbing and furnishing labour or materials or both. That authority separates this tier from the journeyman tier, whose holders must be employed and supervised by a licensed plumbing contractor and may not contract on their own account.
The examination at a glance
| Item | Verified position |
|---|---|
| Program | Oklahoma Plumbing Contractor (unlimited) — the top examined tier under the Plumbing License Law of 1955 |
| Regulator | Oklahoma Construction Industries Board (CIB), under Title 59, sections 1001 et seq., and OAC Title 158, Chapter 30 |
| Examination vendor | PSI Services LLC — Candidate Information Bulletin effective September 11, 2026 |
| Examination structure | Two portions, both required: Trade (Plumbing Contractor and Natural Gas) — 85 questions, 180 minutes, open book; Plumbing Business and Law — 50 questions, 120 minutes, open book |
| Passing standards | Trade portion: 70% (60 of 85), effective November 1, 2026. Business and Law portion: 75% (37 of 50). The two standards are stated separately, as published |
| Tested editions | Candidate choice: the 2018 or 2024 editions of the International Plumbing Code and the International Fuel Gas Code, each with Oklahoma Revisions — see the transition section below |
| Examination fee | $92 per portion through PSI — $184 for a contractor candidate’s two portions |
| Licensing total | $330.00 to the Construction Industries Board: a $300.00 licence fee plus a $30.00 application processing fee |
| Practical component | None. Every portion is a computer-administered, open-book examination; isometric content is analysis inside the trade portion, not drawing production |
| Administrator note | PassProfessor is independent and is not affiliated with the Oklahoma Construction Industries Board |
Two portions, both required
A contractor candidate must take and pass both portions. The trade portion, headed Plumbing Contractor and Natural Gas, presents 85 questions in 180 minutes, open book. The Plumbing Business and Law portion presents 50 questions in 120 minutes, open book. Journeyman candidates take the trade portion only — the Business and Law portion is a defining addition of the contractor tier, and even a contractor applicant arriving by reciprocity must pass the Oklahoma Plumbing Contractor Business and Law portion, together with the bond and insurance requirements below.
Delivery is computer-administered: one question on screen at a time, with return-and-change permitted, and the score given immediately on screen. Candidates bring their own references, highlighted, underlined, and indexed before the session only — no writing in references before or during the sitting, on pain of confiscation and a report — with permanent tabs only, and a silent, non-printing, non-programmable calculator is permitted. Eligibility is determined by the Board, not the vendor; once approved, the candidate contacts PSI to schedule, and there is no expiration on that eligibility. The companion guide at /oklahoma-master-plumber-exam-guide/ states the sitting mechanics in full.
The passing standards, stated in their published split form
The published record states them in two parts: trade 70% — 60 of 85 — effective November 1, 2026, and Business and Law 75% — 37 of 50, the printed raw figure. No single Oklahoma pass percentage exists to quote.
What the two portions cover
All four Oklahoma trade examinations share one identical ten-topic outline totalling 85 questions, followed in full by the unlimited trade portion: General Plumbing Knowledge and Regulations — 10. Water Supply — 10. Drains and Sewers — 10. Fuel Gas — 10. Vents — 13. Piping, Valves, and Control Valves — 8. Fixtures and Equipment — 8. Isometric Analysis — 7. Traps, Interceptors, Indirect, and Special Waste — 5. Safety — 4. Venting is the largest single topic.
Isometric Analysis needs one precise statement: it exists only as a topic inside the written trade examination — seven items analysing isometric drawings. Candidates do not produce a drawing, and no practical, hands-on, or separately administered drawing component exists in any Oklahoma plumbing examination, so a written program can address the full documented tested examination, including this block.
The Business and Law outline totals 50 questions: Bidding and Estimating — 10. Financial — 8. Project Management and Supervision — 7. Licensing Requirements — 6. Contracts — 5. Labor and Personnel — 5. Payroll and Payroll Taxes — 5. Risk Management — 4. Its references include the Board’s Unofficial Administrative Rules and Courtesy Exam Study Aids Book (current edition), the Oklahoma Plumbing License Law of 1955, OAC Title 158 Chapters 30 and 10, Oklahoma Lien Law, the NASCLA Contractors Guide to Business, Law and Project Management, Basic 14th Edition, and the Oklahoma Workers’ Compensation Act. Trade references for the unlimited examination are the International Plumbing Code and the International Fuel Gas Code in the tested editions below, Mathematics for Plumbers and Pipefitters, 8th Edition, 2013, and OSHA 29 CFR Part 1926. The residential trade examinations list the International Residential Code with OSHA and Mathematics — no plumbing code and no fuel gas code — one more reason the residential licence is stated separately here.
Tested edition and adopted code: a choice window inside a transition
Oklahoma is mid-transition, and any page that calls it simply a 2018 state or simply a 2024 state is wrong in opposite directions. The adopted layer is settled: effective September 14, 2026, the statewide minimum codes adopted by the Oklahoma Uniform Building Code Commission — the separate body that adopts codes, while the Construction Industries Board licenses people — are the 2024 editions of the International Plumbing Code, the International Residential Code, and the International Fuel Gas Code, each as amended and modified by the Commission. The 2021 editions were expressly not adopted for any purpose, and no International Plumbing Code 2024 appendices are adopted in the statewide minimum, though local jurisdictions may adopt them. Before that date, the adopted editions were the 2018 editions.
The tested layer for the unlimited trade examinations is currently a candidate choice: the 2018 or the 2024 editions of the International Plumbing Code and the International Fuel Gas Code, each with Oklahoma Revisions; the 2024 code could be used starting October 8, 2026. The same choice applies to the International Residential Code for the residential trade examinations.
One point is contested between primary sources, and this page states no single answer for it: the date the 2018 editions retire from the unlimited examinations. The PSI bulletin prints December 14, 2026, while the Board’s own transition notice runs the transition through January 8, 2027, with 2024-only testing beginning January 9, 2027. Both dates stand in the official record; they cannot both govern. Candidates sitting in that window should confirm their position with the Board and the current bulletin, and tag their study to the edition they will actually sit.
Who may sit: experience, substitution, and reciprocity
All applicants must be 18 years of age or older. The contractor requirement builds directly on the journeyman requirement: the same requirements as a journeyman plumber applicant, with an additional one year of experience — four years in total. The journeyman base is three years of experience in the plumbing trade while employed by a licensed plumbing contractor, or equivalent verifiable experience in the trade while serving in the United States Armed Forces, or a verifiable out-of-state plumbing licence, current and in good standing. One year of verifiable experience is 2,000 hours, and experience obtained in Oklahoma counts only while the applicant maintains an apprentice registration on file, subject to the rules’ military, federal, and state-law exceptions.
Formal education substitutes at a published scale: a Committee-approved associate degree or vocational diploma from a formal plumbing program of at least 1,000 classroom hours substitutes for two years; 500 hours for one year; 375 hours for three-quarters of a year; 334 hours for two-thirds; 250 hours for one-half. A licensed plumber may supervise up to three apprentice plumbers, both employed by the same contractor.
Reciprocity is narrow and named. Arkansas is the only state named in the primary record — under a multi-year agreement with the Arkansas Committee of Plumbing Examiners effective October 21, 2024 — on journeyman-level terms: eligible applicants who held their licence at least one year, hold at least an unlimited journeyman licence, and passed a sponsored examination do not retake the journeyman test, while fees, continuing education, insurance, and all other state-specific requirements still apply. A contractor applicant by reciprocity receives a journeyman licence by reciprocity and earns the contractor licence only upon passing the Oklahoma Business and Law portion and meeting bond and insurance. Regular examinations must be held at least twice each year.
Fees and activation, in their separate layers
The vendor layer and the Board layer are stated separately, as they are charged. Through PSI, each portion costs $92, not refundable or transferable, per registration whether a first attempt or a repeat — $184 across a contractor candidate’s two portions. To the Board, the Plumbing Contractor total is $330.00: a $300.00 licence fee plus a $30.00 application processing fee; the Residential Plumbing Contractor carries the same total. Contractor renewal is $200, with a $100 late fee. The statute frames these as not-to-exceed caps: application $30, examination administration $200, licence issuance $300, renewal $200.
Passing is not the last step. A contractor licence stays inactive until both activation items are received: a $5,000 corporate surety bond payable to the Board, and a certificate of insurance evidencing a minimum $50,000 commercial general liability policy. The term runs no longer than one year, expiring on the last day of the licensee’s birth month. Renewal requires at least six hours of continuing education every three years — every 36 months preceding expiration — in a Committee-approved course covering the adopted codes and revisions or other approved trade-related subjects; a licensee is exempt for three years from passing the current licensing examination, and no licence may be renewed unless the required education is complete.
What the PassProfessor program will cover
Both portions, at their own standards. The program prepares the trade portion and the Plumbing Business and Law portion as the two distinct sittings they are — trade depth across the shared ten-topic outline, with venting given its printed weight, and a full Business and Law strand built on the Oklahoma references, from licensing requirements and lien law through payroll taxes and risk management.
Edition discipline through the transition. Because the tested edition is currently a candidate choice, the program teaches candidates to work with an edition tag in view: to study the International Plumbing Code and the International Fuel Gas Code with Oklahoma Revisions in the edition that governs their sitting, and to treat any answer that changes between the 2018 and 2024 editions as an edition question first.
The Oklahoma structure taught as part of the subject. The retired name and the contractor title that replaced it, the Board that licenses and the separate Commission that adopts codes, the unlimited and residential licences kept distinct, the bond-and-insurance activation step, and the birth-month licence term are all taught as examined context — because the licensing structure is itself part of what the Business and Law portion examines.
Independence, stated plainly. PassProfessor is an independent preparation provider, not affiliated with the Oklahoma Construction Industries Board, and this program is not a Board course. Completing it confers no licence and no eligibility; the Board alone licenses and determines eligibility, and candidates schedule through PSI after Board approval. For the full breakdown, read the companion guide at /oklahoma-master-plumber-exam-guide/.
Tell me when enrollment opens. The Oklahoma Plumbing Contractor program is in the works and enrollment is not yet open. Leave an email address and PassProfessor will write to you when the program is ready — and only about this program. No date is promised.
Frequently asked questions
Is there an Oklahoma master plumber licence?
No. Title 59, section 1003(7) defines the older term only to retire it — a person formerly known by that term is henceforth to be known as a plumbing contractor.
Who licenses Oklahoma plumbing contractors?
The Oklahoma Construction Industries Board, under the Plumbing License Law of 1955 and OAC Title 158, Chapter 30, advised by the Oklahoma State Committee of Plumbing Examiners. Code adoption belongs to the separate Oklahoma Uniform Building Code Commission.
What scores pass?
Trade: 70% — 60 of 85 — effective November 1, 2026. Business and Law: 75% — 37 of 50. Stated separately, as published.
When does the 2018 edition retire from the unlimited examinations?
The record is contested: the PSI bulletin prints December 14, 2026, while the Board’s notice runs the transition through January 8, 2027 with 2024-only testing beginning January 9, 2027. This page states no single date; confirm with the Board for a sitting in that window.
Is there a practical or drawing-production examination?
No. Isometric Analysis is a seven-item analysis topic inside the trade portion; candidates analyse drawings and do not produce one.
What experience does the contractor tier require?
The journeyman requirements plus one additional year — four years in total — at age 18 or older, with the substitution scale described on this page.
How does the Residential Plumbing Contractor differ?
A separate licence with a separate trade examination built on the International Residential Code — no plumbing or fuel gas code among its references — while the unlimited examination is built on both of those codes.
Is PassProfessor affiliated with the Construction Industries Board?
No. PassProfessor is an independent preparation provider. The Board alone licenses plumbing contractors and determines examination eligibility.